AIM ¶ 3-4-8 — National Security Areas
AIM 3-4-8 explains National Security Areas: voluntary avoidance, possible NOTAM prohibitions under 14 CFR 99.7, and what pilots should know.
National Security Areas (NSAs) are blocks of airspace with defined vertical and lateral dimensions established around ground facilities that require increased security and safety. They appear as depicted areas on aeronautical charts.
Key points from AIM 3-4-8:
- Pilots are requested to voluntarily avoid flying through a depicted NSA. This is a recommended practice, not a regulatory mandate by default.
- When greater security is needed, flight through an NSA can be temporarily prohibited by regulation under 14 CFR 99.7.
- Any regulatory prohibition is issued by System Operations Security and disseminated via NOTAM — so always check NOTAMs before a flight near an NSA.
- Questions about NSAs should be directed to System Operations Security.
Operationally, this means a routine NSA only asks for your cooperation, but a NOTAM can convert it into a hard no-fly zone. Treat NSAs as a NOTAM-check item during preflight planning, especially on cross-countries that pass near sensitive ground sites.
Five FAA-written-style questions. Instant explanations, every answer cites its source — no account needed.
What is required before you may operate an aircraft within Class B airspace?